What does "hydrometric" mean?

Hydrometric: Of or pertaining to measurement of the velocity, discharge, etc., of running water.

Additional senses

  1. 2.Made by means of an hydrometer; as, hydrometric observations. Hydrometric pendulum, a species of hydrometer consisting of a hollow ball of ivory or metal suspended by a treated from the center of a graduated quadrant, and held in a stream to measure the velocity of the water by the inclination given to the thread; a kind of current gauge.

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